As the Federal Communications Commission considers whether, and how, to utilize spectrum at 6 GHz for unlicensed use, a group of tech and Wi-Fi companies that includes Facebook, Apple, Microsoft and Google has thrown its support behind providing additional room for Wi-Fi to grow.
In a filing with the FCC, the coalition of nearly three dozen companies said that “Wi-Fi has become the single most important wireless technology for American consumers and businesses,” and that “moving forward and opening up the 6 GHz band is critical. It has been more than twenty years since new mid-band spectrum was made available for Wi-Fi and other unlicensed uses, causing a severe shortage for a wireless technology that handles 75% of mobile data traffic.”
In addition to the four tech giants, other companies which support 6 GHz for unlicensed use included chip companies such as Qualcomm, Broadcom, Intel, Marvell and Qorvo; cable companies including Charter Communications; the Wireless Internet Service Providers Association (WISPA); and other industry players such as Boingo Wireless, Cisco, Extreme Networks, HP and Hewlett Packard Enterprise, Philips and Sony.
Late last year, the Federal Communications Commission put forward a proposal that would open up 1200 megahertz of spectrum for use by unlicensed devices in the 6 GHz band, at 5.925-7.125 GHz. One of the sticking points has been how to navigate coexistence in the band between incumbent users and new, unlicensed users.
The coalition of companies in favor of unlicensed use said that the unlicensed community “has been steadfastly working with technical experts and conducting detailed engineering analyses that demonstrate how coexistence … s will work. These analyses include very-low-power (VLP) and low-power indoor (LPI) devices and use cases that will be deployed quickly, in addition to an Automated Frequency Control (AFC) system to ensure standard-power unlicensed devices do not cause harmful interference.”
However, another recent filing lays out some of the opposition to unlicensed use at 6 GHz from incumbents, who worry that the microwave links on which their networks depend will be at risk. That filing, from 11 associations including the Utilities Technology Council, International Association of Fire Chiefs and trade associations for gas, petroleum, railroads and rural electric cooperatives and nearly 60 individual utility companies, says that because of the risk to interference with their mission-critical networks, “unlicensed operations should only be permitted in the 6 GHz band if the Commission adopts more stringent interference protections for co-channel and adjacent channel microwave systems, including proven technology to mitigate the risk of interference by prior coordination of unlicensed operations, as discussed below.
“We are very concerned that the proposed mitigation scheme for protecting public safety and CII users from interference—the Automated Frequency Coordination (AFC) system—is theoretical in nature and has not been tested or proven to work,” those groups said, and added that the “current proposal does not contemplate a mechanism for ensuring that unlicensed users take responsibility for the cost impact of the interference resulting from unlicensed devices operating in the 6 GHz band.
“Given the significant risk that allowing unlicensed operations in the 6 GHz band could have on mission-critical communications networks, at the very least, the Commission should consider working with one or more federal laboratories to ensure that the untested interference mitigation measures proposed in the rulemaking will work before unlicensed operations are allowed in the 6 GHz band,” the filing said.―RCR Wireless News